PARTITION-FUNCTION VERSUS BOUNDARY-CONDITIONS AND CONFINEMENT IN THE YANG-MILLS THEORY - ART. NO. 085024

We analyze the dependence of the partition function on the boundary co ndition for the longitudinal component of the electric field strength in gauge field theories. In a physical gauge the Gauss law constraint may be resolved explicitly expressing this component via an integral o f the physical transversal variables. In particular, we study quantum electrodynamics with an external charge and SU(2) gluodynamics. We fin d that only a charge distribution slowly decreasing at spatial infinit y can produce a nontrivial dependence in the Abelian theory. However, in gluodynamics for temperatures below some critical value the partiti on function acquires a delta-function-like dependence on the boundary condition, which leads to color confinement. [S0556-2821(98)02320-0].